U.S. patent number 8,211,080 [Application Number 12/020,276] was granted by the patent office on 2012-07-03 for absorbent article with improved fastening system and method of fastening thereof.
This patent grant is currently assigned to Kimberly-Clark Worldwide, Inc.. Invention is credited to Kathleen I. Ratliff, Marcille F. Ruman, Lindsay C. Shelley.
United States Patent |
8,211,080 |
Ruman , et al. |
July 3, 2012 |
Absorbent article with improved fastening system and method of
fastening thereof
Abstract
A method of securing an absorbent article in a fastened
configuration for personal wear includes forming an absorbent
article to have a body. A mechanical fastening system is positioned
on the body. The mechanical fastening system has a loop component
and a hook component. The loop component is an elastomeric laminate
formed by securing an elastomeric loop material to an elastomeric
substrate. The hook component is fastenably engageable with the
loop material of the loop component. The laminate is stretched
which includes stretching both the loop material and the substrate.
The hook component and the loop component are engaged whereby the
hook component fastenably engages the loop material of the loop
component. The stretched laminate is allowed to retract which
includes retraction of the loop material and retraction of the
substrate.
Inventors: |
Ruman; Marcille F. (Neenah,
WI), Shelley; Lindsay C. (Appleton, WI), Ratliff;
Kathleen I. (Oshkosh, WI) |
Assignee: |
Kimberly-Clark Worldwide, Inc.
(Neenah, WI)
|
Family
ID: |
21901947 |
Appl.
No.: |
12/020,276 |
Filed: |
January 25, 2008 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20080119817 A1 |
May 22, 2008 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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10038796 |
Dec 31, 2001 |
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Current U.S.
Class: |
604/391; 604/387;
604/386 |
Current CPC
Class: |
A61F
13/565 (20130101); A61F 13/622 (20130101); A61F
13/5633 (20130101); A61F 13/15756 (20130101) |
Current International
Class: |
A61F
13/15 (20060101); A61F 13/20 (20060101) |
Field of
Search: |
;604/386,389-392 |
References Cited
[Referenced By]
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WO |
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Primary Examiner: Zalukaeva; Tatyana
Assistant Examiner: Su; Susan
Attorney, Agent or Firm: Armstrong Teasdale LLP
Parent Case Text
CROSS REFERENCE TO RELATED APPLICATION
This application is a continuation application of U.S. patent
application Ser. No. 10/038,796, filed Dec. 31, 2001, which is
hereby incorporated by reference in its entirety.
Claims
What is claimed is:
1. A method of securing an absorbent article in a fastened
configuration for personal wear, said method comprising: forming an
absorbent article to have a body having first and second end
regions, the body comprising an inner layer for contact with a
wearer's skin wherein at least a portion of said inner layer is
liquid permeable, an outer layer in opposed relation with the inner
layer, and an absorbent layer disposed between the inner layer and
the outer layer; positioning a mechanical fastening system on the
body, the mechanical fastening system comprising a loop component
and a hook component, the loop component comprising an elastomeric
laminate including an elastomeric loop material and an elastomeric
substrate, the hook component being fastenably engageable with the
loop material of the loop component; stretching the laminate which
includes stretching both said loop material and said substrate;
engaging the hook component and the loop component whereby the hook
component fastenably engages the loop material of the loop
component; and allowing the stretched laminate to retract which
includes retraction of said loop material and retraction of said
substrate; wherein the body of the absorbent article includes side
panels, and wherein positioning the mechanical fastening system on
the body comprises positioning the hook component on the side
panels of the body.
2. The method of claim 1 wherein positioning the mechanical
fastening system on the body comprises positioning the loop
component on the side panels of the body.
3. The method of claim 2 wherein engaging the hook and loop
components forms a refastenable side seam.
4. A method of securing an absorbent article in a fastened
configuration for personal wear, said method comprising: forming an
absorbent article to have a body having first and second end
regions, the body comprising an inner layer for contact with a
wearer's skin wherein at least a portion of said inner layer is
liquid permeable, an outer layer in opposed relation with the inner
layer, and an absorbent layer disposed between the inner layer and
the outer layer; positioning a mechanical fastening system on the
body, the mechanical fastening system comprising a loop component
and a hook component, the loop component comprising an elastomeric
laminate including an elastomeric loop material and an elastomeric
substrate, the hook component being fastenably engageable with the
loop material of the loop component; stretching the laminate which
includes stretching both said loop material and said substrate;
engaging the hook component and the loop component whereby the hook
component fastenably engages the loop material of the loop
component; and allowing the stretched laminate to retract which
includes retraction of said loop material and retraction of said
substrate; wherein the body has a longitudinal axis and a
transverse axis, and wherein the step of positioning a mechanical
fastening system on the body comprises affixing the loop component
on the body such that the loop component is generally parallel to
the longitudinal axis of the body.
5. The method of claim 4 wherein the step of positioning a
mechanical fastening system on the body comprises affixing the hook
component on the body such that the hook component is generally
parallel to the longitudinal axis of the body.
6. A method of securing an absorbent article in a fastened
configuration for personal wear, said method comprising: forming an
absorbent article to have a body having first and second end
regions, the body comprising an inner layer for contact with a
wearer's skin wherein at least a portion of said inner layer is
liquid permeable, an outer layer in opposed relation with the inner
layer, and an absorbent layer disposed between the inner layer and
the outer layer; positioning a mechanical fastening system on the
body, the mechanical fastening system comprising a loop component
and a hook component, the loop component comprising an elastomeric
laminate including an elastomeric loop material and an elastomeric
substrate, the hook component being fastenably engageable with the
loop material of the loop component; stretching the laminate which
includes stretching both said loop material and said substrate;
engaging the hook component and the loop component whereby the hook
component fastenably engages the loop material of the loop
component; and allowing the stretched laminate to retract which
includes retraction of said loop material and retraction of said
substrate; wherein the step of stretching the laminate comprises
stretching the laminate in a direction generally transverse to a
longitudinal axis of the body.
Description
BACKGROUND
The present invention pertains to absorbent articles, such as
training pants, diapers, incontinence garments and the like, and
more particularly, to a mechanical fastening system for such
absorbent articles.
Such absorbent articles generally comprise a liquid-impermeable
barrier sheet, a liquid permeable body side liner and an absorbent
medium between them. They generally include some type of attaching
system for fitting the article to the wearer. In many such
applications, the fastening system is preferably refastenable so
that the article can be temporarily removed and then refastened to
the wearer.
One common form of mechanical attachment systems is the so called
hook-and-loop system which comes in various forms and has both
advantages and disadvantages in its application to such absorbent
articles. For example, particularly with disposable diapers, the
fasteners are secured to the garment in the front and back,
generally in such a manner that the hook portions of the fasteners
on each side are pulled over the loop portions to secure the
garment to the wearer. In typical such installations the loop
material is relatively unstretchable and either forms a portion of
the garment itself or is attached to the surface of the garment.
The hook panel is generally stretchable while the hook is generally
unstretchable so that it can be positioned on the loop material for
adjustment to the size and shape of the wearer of the garment.
A disadvantage of this type of hook-and-loop system is the tendency
of the hooks to separate from the loop material when the wearer is
active, such as when stooping or bending as is common with a child
in training pants. This disengagement failure can result in
requiring it to be refastened. This produces an undesirable
inconvenience and disadvantage of such a mechanical fastening
system for such applications. In an attempt to overcome this
disadvantage many systems have increased the force to disengage
through various enhancements to maximize the hook-and-loop material
interaction.
SUMMARY OF THE INVENTION
In one aspect, a method of securing an absorbent article in a
fastened configuration for personal wear generally comprises
forming an absorbent article to have a body having first and second
end regions. The body comprises an inner layer for contact with a
wearer's skin wherein at least a portion of the inner layer is
liquid permeable, an outer layer in opposed relation with the inner
layer, and an absorbent layer disposed between the inner layer and
the outer layer. A mechanical fastening system is positioned on the
body. The mechanical fastening system comprises a loop component
and a hook component. The loop component comprises an elastomeric
laminate formed by securing an elastomeric loop material to an
elastomeric substrate. The hook component is fastenably engageable
with the loop material of the loop component. The laminate is
stretched which includes stretching both the loop material and the
substrate. The hook component and the loop component are engaged
whereby the hook component fastenably engages the loop material of
the loop component. The stretched laminate is allowed to retract
which includes retraction of the loop material and retraction of
the substrate.
In another aspect, fastening components of an article comprise a
hook component and a loop component. The loop component comprises a
laminate formed by securing a stretchable loop material to a
stretchable substrate. The hook component is capable of fastening
engagement with the loop material of the loop component. A method
for securing engagement between the fastening components of the
article generally comprise the steps of arranging the fastening
components in at least partially opposed relationship with each
other. The fastening components are engaged with each other to
define an engagement seam whereby the hook component fastenably
engages the loop material of the loop component. The loop component
is contracted relative to the hook component at the engagement seam
following engagement of the fastening components to thereby move
one fastening component relative to the other fastening component
at the engagement seam to promote increased engagement between the
fastening components at the engagement seam. The contracting step
includes contracting the laminate which includes contracting the
stretchable loop material and contracting the stretchable
substrate.
Definitions
Within the context of this specification, each term or phrase below
will include the following meaning or meanings.
"Bonded" refers to the joining, adhering, connecting, attaching, or
the like, of two elements. Two elements will be considered to be
bonded together when they are bonded directly to one another or
indirectly to one another, such as when each is directly bonded to
intermediate elements.
"Comprising" is inclusive or open-ended and does not exclude
additional, unrecited elements or method steps.
"Connected" refers to the joining, adhering, bonding, attaching, or
the like, of two elements. Two elements will be considered to be
connected together when they are connected directly to one another
or indirectly to one another, such as when each is directly
connected to intermediate elements.
"Disposable" refers to articles which are designed to be discarded
after a limited use rather than being laundered or otherwise
restored for reuse.
"Disposed," "disposed on," and variations thereof are intended to
mean that one element can be integral with another element, or that
one element can be a separate structure bonded to or placed with or
placed near another element.
"Elastic," "elasticized" and "elasticity" mean that property of a
material or composite by virtue of which it tends to recover its
original size and shape after removal of a force causing a
deformation.
"Elastomeric" refers to a material or composite which can be
elongated by at least 25 percent of its relaxed length and which
will recover, upon release of the applied force, at least 10
percent of its elongation. It is generally preferred that the
elastomeric material or composite be capable of being elongated by
at least 75 percent, particularly at least 150 percent, and more
particularly at least 350 percent, of its relaxed length and
recover, upon release of an applied force, at least 50 percent of
its elongation.
"Fabrics" is used to refer to all of the woven, knitted and
nonwoven fibrous webs.
"Flexible" refers to materials which are compliant and which will
readily conform to the general shape and contours of the wearer's
body.
"Force" includes a physical influence exerted by one body on
another which produces acceleration of bodies that are free to move
and deformation of bodies that are not free to move. Force is
expressed in grams per unit area.
"Graphic" refers to any design, pattern, or the like that is
visible on an absorbent article.
"Hydrophilic" describes fibers or the surfaces of fibers which are
wetted by the aqueous liquids in contact with the fibers. The
degree of wetting of the materials can, in turn, be described in
terms of the contact angles and the surface tensions of the liquids
and materials involved. Equipment and techniques suitable for
measuring the wettability of particular fiber materials or blends
of fiber materials can be provided by a Cahn SFA-222 Surface Force
Analyzer System, or a substantially equivalent system. When
measured with this system, fibers having contact angles less than
90.degree. are designated "wettable" or hydrophilic, while fibers
having contact angles greater than 90.degree. are designated
"nonwettable" or hydrophobic.
"Integral" is used to refer to various portions of a single unitary
element rather than separate structures bonded to or placed with or
placed near one another.
"Inward" and "outward" refer to positions relative to the center of
an absorbent article, and particularly transversely and/or
longitudinally closer to or away from the longitudinal and
transverse center of the absorbent article.
"Layer" when used in the singular can have the dual meaning of a
single element or a plurality of elements.
"Liquid impermeable", when used in describing a layer or
multi-layer laminate, means that a liquid, such as urine, will not
pass through the layer or laminate, under ordinary use conditions,
in a direction generally perpendicular to the plane of the layer or
laminate at the point of liquid contact. Liquid, or urine, may
spread or be transported parallel to the plane of the liquid
impermeable layer or laminate, but this is not considered to be
within the meaning of "liquid impermeable" when used herein.
"Longitudinal" and "transverse" have their customary meaning, as
indicated by the longitudinal and transverse axes depicted in FIGS.
2 and 3. The longitudinal axis lies in the plane of the article and
is generally parallel to a vertical plane that bisects a standing
wearer into left and right body halves when the article is worn.
The transverse axis lies in the plane of the article generally
perpendicular to the longitudinal axis. The article as illustrated
is longer in the longitudinal direction than in the transverse
direction.
"Member" when used in the singular can have the dual meaning of a
single element or a plurality of elements.
"Nonwoven" and "nonwoven web" refer to materials and webs of
material which are formed without the aid of a textile weaving or
knitting process.
"Operatively joined," with reference to the attachment of an
elastic member to another element, means that the elastic member
when attached to or connected to the element, or treated with heat
or chemicals, by stretching, or the like, gives the element elastic
properties; and with reference to the attachment of a non-elastic
member to another element, means that the member and element can be
attached in any suitable manner that permits or allows them to
perform the intended or described function of the joinder. The
joining, attaching, connecting or the like can be either directly,
such as joining either member directly to an element, or can be
indirectly by means of another member disposed between the first
member and the first element.
"Outer cover graphic" refers to a graphic that is directly visible
upon inspection of the exterior surface of a garment, and for a
refastenable garment is in reference to inspection of the exterior
surface of the garment when the fastening system is engaged as it
would be during use.
"Permanently bonded" refers to the joining, adhering, connecting,
attaching, or the like, of two elements of an absorbent garment
such that the elements tend to be and remain bonded during normal
use conditions of the absorbent garment.
"Refastenable" refers to the property of two elements being capable
of releasable attachment, separation, and subsequent releasable
reattachment without substantial permanent deformation or
rupture.
"Releasably attached," "releasably engaged" and variations thereof
refer to two elements being connected or connectable such that the
elements tend to remain connected absent a separation force applied
to one or both of the elements, and the elements being capable of
separation without substantial permanent deformation or rupture.
The required separation force is typically beyond that encountered
while wearing the absorbent garment.
"Rupture" means the breaking or tearing apart of a material; in
tensile testing, the term refers to the total separation of a
material into two parts either all at once or in stages, or the
development of a hole in some materials.
"Stretch bonded" refers to an elastic member being bonded to
another member while the elastic member is extended at least about
25 percent of its relaxed length. Desirably, the term "stretch
bonded" refers to the situation wherein the elastic member is
extended at least about 100 percent, and more desirably at least
about 300 percent, of its relaxed length when it is bonded to the
other member.
"Stretch bonded laminate" refers to a composite material having at
least two layers in which one layer is a gatherable layer and the
other layer is an elastic layer. The layers are joined together
when the elastic layer is in an extended condition so that upon
relaxing the layers, the gatherable layer is gathered.
"Surface" includes any layer, film, woven, nonwoven, laminate,
composite, or the like, whether pervious or impervious to air, gas,
and/or liquids.
"Tension" includes a uniaxial force tending to cause the extension
of a body or the balancing force within that body resisting the
extension.
"Thermoplastic" describes a material that softens when exposed to
heat and which substantially returns to a nonsoftened condition
when cooled to room temperature.
These terms may be defined with additional language in the
remaining portions of the specification.
BRIEF DESCRIPTION OF THE DRAWINGS
The above-mentioned and other features of the present invention and
the manner of attaining them will become more apparent, and the
invention itself will be better understood by reference to the
following description and the accompanying drawings, wherein
similar features in different figures have been given the same
reference numeral.
FIG. 1 illustrates a side view of a training pant suitable for use
with the process and apparatus according to the present invention,
where the fastening system is shown engaged on one side of the
training pant and disengaged on the other side of the training
pant.
FIG. 2 illustrates a plan view of the training pant shown in FIG. 1
in an unfastened, stretched and laid flat condition, and showing
the surface of the training pant that faces away from the
wearer.
FIG. 3 illustrates a plan view similar to FIG. 2, but showing the
surface of the training pant that faces the wearer when the
training pant is worn, and with portions cut away to show the
underlying features.
FIG. 4 illustrates an alternative embodiment of the present
invention in a side view similar to FIG. 1.
FIG. 5 is a plan view of the embodiment of FIG. 4 in a similar
position as FIG. 3.
FIG. 6 schematically illustrates a flow diagram for manufacture of
one embodiment of a pant according to the present invention.
FIG. 7 illustrates a pant according to one embodiment of the
present invention at three stages during manufacture.
DETAILED DESCRIPTION OF THE DRAWINGS
FIG. 1 representatively illustrates one embodiment of training pant
20 in a partially fastened condition. The training pant 20
comprises an absorbent body 32 and a fastening system 80. The
absorbent body 32 defines a front waist region 22, a back waist
region 24, a crotch region 26 interconnecting the front and back
waist regions, an inner surface 28 which is configured to contact
the wearer, and an outer surface 30 opposite the inner surface
which is configured to contact the wearer's clothing. With
additional reference to FIGS. 2 and 3, the absorbent body 32 also
defines a pair of transversely opposed side edges 36 and a pair of
longitudinally opposed waist edges, which are designated front
waist edge 38 and back waist edge 39. The front waist region 22 is
contiguous with the front waist edge 38, and the back waist region
24 is contiguous with the back waist edge 39.
The illustrated absorbent body 32 comprises a rectangular composite
structure 33, a pair of transversely opposed front side panels 34,
and a pair of transversely opposed back side panels 134. The
composite structure 33 and side panels 34 and 134 may be integrally
formed or comprise two or more separate elements, as shown in FIG.
1. The illustrated composite structure 33 comprises an outer cover
40, a bodyside liner 42 (FIG. 3) which is connected to the outer
cover in a superposed relation, an absorbent assembly 44 (FIG. 3)
which is located between the outer cover and the bodyside liner,
and a pair of containment flaps 46 (FIG. 3). The illustrated
composite structure 33 has opposite linear end edges 45 that form
portions of the front and back waist edges 38 and 39, and opposite
linear side edges 47 that form portions of the side edges 36 of the
absorbent body 32 (FIGS. 2 and 3). For reference, arrows 48 and 49
depicting the orientation of the longitudinal axis and the
transverse axis, respectively, of the training pant 20 are
illustrated in FIGS. 2 and 3.
With the training pant 20 in the fastened position as partially
illustrated in FIG. 1, the front and back waist regions 22 and 24
are joined together to define a three-dimensional pant
configuration having a waist opening 50 and a pair of leg openings
52. The front waist region 22 comprises the portion of the training
pant 20 which, when worn, is positioned on the front of the wearer
while the back waist region 24 comprises the portion of the
training pant which, when worn, is positioned on the back of the
wearer. The crotch region 26 of the training pant 20 comprises the
portion of the training pant which, when worn, is positioned
between the legs of the wearer and covers the lower torso of the
wearer. The front and back side panels 34 and 134 comprise the
portions of the training pant 20 which, when worn, are positioned
on the hips of the wearer.
The front waist region 22 of the absorbent body 32 includes the
transversely opposed front side panels 34 and a front center panel
35 (FIGS. 2 and 3) positioned between and interconnecting the side
panels. The back waist region 24 of the absorbent body 32 includes
the transversely opposed back side panels 134 and a back center
panel 135 (FIGS. 2 and 3) positioned between and interconnecting
the side panels. The waist edges 38 and 39 of the absorbent body 32
are configured to encircle the waist of the wearer when worn and
provide the waist opening 50 which defines a waist perimeter
dimension. Portions of the transversely opposed side edges 36 in
the crotch region 26 generally define the leg openings 52. The
waist regions 22 and 24 jointly define a waistband 75 (FIGS. 1, 4
and 7) that peripherally surrounds the waist opening 50 of the pant
20. The waist regions 22 and 24 also jointly define a hip section
77 (FIGS. 1, 4 and 7) that encircles the pant 20 and is disposed
between the waistband 75 and the leg openings 52.
The absorbent body 32 is configured to contain and/or absorb any
body exudates discharged from the wearer. For example, the
absorbent body 32 desirably although not necessarily comprises the
pair of containment flaps 46 which are configured to provide a
barrier to the transverse flow of body exudates. A flap elastic
member 53 (FIG. 3) is operatively joined with each containment flap
46 in any suitable manner as is well known in the art. The
elasticized containment flaps 46 define an unattached edge which
assumes an upright configuration in at least the crotch region 26
of the training pant 20 to form a seal against the wearer's body.
The containment flaps 46 can be located along the transversely
opposed side edges of the absorbent body 32, and can extend
longitudinally along the entire length of the absorbent body or may
only extend partially along the length of the absorbent body.
Suitable constructions and arrangements for the containment flaps
46 are generally well known to those skilled in the art and are
described in U.S. Pat. No. 4,704,116 issued Nov. 3, 1987 to Enloe,
which is incorporated herein by reference.
To further enhance containment and/or absorption of body exudates,
the training pant 20 desirably although not necessarily includes a
front waist elastic member 54, a rear waist elastic member 56, and
leg elastic members 58, as are known to those skilled in the art
(FIG. 3). The waist elastic members 54 and 56 can be operatively
joined to the outer cover 40 and/or bodyside liner 42 along the
opposite waist edges 38 and 39, and can extend over part or all of
the waist edges, such that the waist elastic members are disposed
in the waistband 75 in the fully assembled pant. The leg elastic
members 58 are desirably operatively joined to the outer cover 40
and/or bodyside liner 42 along the opposite side edges 36 and
positioned in the crotch region 26 of the training pant 20. The leg
elastic members 58 can be longitudinally aligned along each side
edge 47 of the composite structure 33. Each leg elastic member 58
has a front terminal point 63 and a back terminal point 65, which
points represent the longitudinal ends of the elastic gathering
caused by the leg elastic members. The front terminal points 63 can
be located adjacent the longitudinally innermost parts of the front
side panels 34, and the back terminal points 65 can be located
adjacent the longitudinally innermost parts of the back side panels
134.
The flap elastic members 53, the waist elastic members 54 and 56,
and the leg elastic members 58 can be formed of any suitable
elastic material. As is well known to those skilled in the art,
suitable elastic materials include sheets, strands or ribbons of
natural rubber, synthetic rubber, or thermoplastic elastomeric
polymers. The elastic materials can be stretched and adhered to a
substrate, adhered to a gathered substrate, or adhered to a
substrate and then elasticized or shrunk, for example with the
application of heat; such that elastic constrictive forces are
imparted to the substrate. In one particular embodiment, for
example, the leg elastic members 58 comprise a plurality of
dry-spun coalesced multifilament spandex elastomeric threads sold
under the trade name LYCRA and available from E. I. Du Pont de
Nemours and Company, Wilmington, Del. U.S.A.
In particular embodiments, the waist elastic members 54 and 56 can
be formed of retractive materials. For example, the waist elastic
members 54 and 56 can be formed of an elastomeric material that is
adapted to retract upon activation by a source of heat such as
disclosed in U.S. Pat. No. 4,640,726.
The outer cover 40 desirably comprises a material that is
substantially liquid impermeable, and can be elastic, stretchable
or nonstretchable. The outer cover 40 can be a single layer of
liquid impermeable material, but desirably comprises a
multi-layered laminate structure in which at least one of the
layers is liquid impermeable. For instance, the outer cover 40 can
include a liquid permeable outer layer and a liquid impermeable
inner layer that are suitably joined together by a laminate
adhesive, ultrasonic bonds, thermal bonds, or the like. Suitable
laminate adhesives, which can be applied continuously or
intermittently as beads, a spray, parallel swirls, or the like, can
be obtained from Findley Adhesives, Inc., of Wauwatosa, Wis.
U.S.A., or from National Starch and Chemical Company, Bridgewater,
N.J. U.S.A. The liquid permeable outer layer can be any suitable
material and desirably one that provides a generally cloth-like
texture. One example of such a material is a 20 gsm (grams per
square meter) spunbond polypropylene nonwoven web. The outer layer
may also be made of those materials of which liquid permeable
bodyside liner 42 is made. While it is not a necessity for outer
layer to be liquid permeable, it is desired that it provides a
relatively cloth-like texture to the wearer.
The inner layer of the outer cover 40 can be both liquid and vapor
impermeable, or can be liquid impermeable and vapor permeable. The
inner layer is desirably manufactured from a thin plastic film,
although other flexible liquid impermeable materials may also be
used. The inner layer, or the liquid impermeable outer cover 40
when a single layer, prevents waste material from wetting articles,
such as bedsheets and clothing, as well as the wearer and
caregiver. A suitable liquid impermeable film for use as a liquid
impermeable inner layer, or a single layer liquid impermeable outer
cover 40, is a 0.02 millimeter polyethylene film commercially
available from Huntsman Packaging of Newport News, Va. U.S.A. If
the outer cover 40 is a single layer of material, it can be
embossed and/or matte finished to provide a more cloth-like
appearance. As earlier mentioned, the liquid impermeable material
can permit vapors to escape from the interior of the disposable
absorbent article, while still preventing liquids from passing
through the outer cover 40. A suitable "breathable" material is
composed of a microporous polymer film or a nonwoven fabric that
has been coated or otherwise treated to impart a desired level of
liquid impermeability. A suitable microporous film is a PMP-1 film
material commercially available from Mitsui Toatsu Chemicals, Inc.,
Tokyo, Japan, or an XKO-8044 polyolefin film commercially available
from 3M Company, Minneapolis, Minn. U.S.A.
As shown in FIGS. 1 and 2, the training pant 20 and in particular
the outer cover 40 desirably comprises one or more
appearance-related components. Examples of appearance-related
components include, but are not limited to, graphics; highlighting
or emphasizing leg and waist openings in order to make product
shaping more evident or visible to the user; highlighting or
emphasizing areas of the product to simulate functional components
such as elastic leg bands, elastic waistbands, simulated "fly
openings" for boys, ruffles for girls; highlighting areas of the
product to change the appearance of the size of the product;
registering wetness indicators, temperature indicators, and the
like in the product; registering a back label, or a front label, in
the product; and registering written instructions at a desired
location in the product.
The illustrated training pant 20, which is designed for use by
young girls, includes a registered outer cover graphic 60. In this
design, the registered graphic 60 includes a primary pictorial
image 61, simulated waist ruffles 62, and simulated leg ruffles 64.
The primary pictorial image 61 includes a rainbow, sun, clouds,
animal characters, wagon and balloons. Any suitable design can be
utilized for a training pant intended for use by young girls, so as
to be aesthetically and/or functionally pleasing to them and the
caregiver. The appearance-related components are desirably
positioned on the training pant 20 at selected locations, which can
be carried out using the methods disclosed in U.S. Pat. No.
5,766,389 issued Jun. 16, 1998 to Brandon et al., which is
incorporated herein by reference. The primary pictorial image 61 is
desirably positioned in the front waist region 22 along the
longitudinal centerline of the training pant 20.
The liquid permeable bodyside liner 42 is illustrated as overlying
the outer cover 40 and absorbent assembly 44, and may but need not
have the same dimensions as the outer cover 40. The bodyside liner
42 is desirably compliant, soft feeling, and non-irritating to the
child's skin. Further, the bodyside liner 42 can be less
hydrophilic than the absorbent assembly 44, to present a relatively
dry surface to the wearer and permit liquid to readily penetrate
through its thickness. Alternatively, the bodyside liner 42 can be
more hydrophilic or can have essentially the same affinity for
moisture as the absorbent assembly 44 to present a relatively wet
surface to the wearer to increase the sensation of being wet. This
wet sensation can be useful as a training aid. The
hydrophilic/hydrophobic properties can be varied across the length,
width and depth of the bodyside liner 42 and absorbent assembly 44
to achieve the desired wetness sensation or leakage
performance.
The bodyside liner 42 can be manufactured from a wide selection of
web materials, such as synthetic fibers (for example, polyester or
polypropylene fibers), natural fibers (for example, wood or cotton
fibers), a combination of natural and synthetic fibers, porous
foams, reticulated foams, apertured plastic films, or the like.
Various woven and nonwoven fabrics can be used for the bodyside
liner 42. For example, the bodyside liner can be composed of a
meltblown or spunbonded web of polyolefin fibers. The bodyside
liner can also be a bondedcarded web composed of natural and/or
synthetic fibers. The bodyside liner can be composed of a
substantially hydrophobic material, and the hydrophobic material
can, optionally, be treated with a surfactant or otherwise
processed to impart a desired level of wettability and
hydrophilicity. For example, the material can be surface treated
with about 0.45 weight percent of a surfactant mixture comprising
Ahcovel N-62 from Hodgson Textile Chemicals of Mount Holly, N.C.
U.S.A. and Glucopan 220UP from Henkel Corporation of Ambler, Pa. in
an active ratio of 3:1. The surfactant can be applied by any
conventional means, such as spraying, printing, brush coating or
the like. The surfactant can be applied to the entire bodyside
liner 42 or can be selectively applied to particular sections of
the bodyside liner, such as the medial section along the
longitudinal centerline.
A suitable liquid permeable bodyside liner 42 is a nonwoven
bicomponent web having a basis weight of about 27 gsm. The nonwoven
bicomponent can be a spunbond bicomponent web, or a bonded carded
bicomponent web. Suitable bicomponent staple fibers include a
polyethylene/polypropylene bicomponent fiber available from Chisso
Corporation, Osaka, Japan. In this particular bicomponent fiber,
the polypropylene forms the core and the polyethylene forms the
sheath of the fiber. Other fiber orientations are possible, such as
multi-lobe, side-by-side, end-to-end, or the like.
The absorbent assembly 44 (FIG. 3) is positioned between the outer
cover 40 and the bodyside liner 42, which components can be joined
together by any suitable means such as adhesives, ultrasonic bonds,
thermal bonds, or the like. The absorbent assembly 44 can be any
structure which is generally compressible, conformable,
non-irritating to the child's skin, and capable of absorbing and
retaining liquids and certain body wastes. The absorbent assembly
44 can be manufactured in a wide variety of sizes and shapes, and
from a wide variety of liquid absorbent materials commonly used in
the art. For example, the absorbent assembly 44 can suitably
comprise a matrix of hydrophilic fibers, such as a web of
cellulosic fluff, mixed with particles of a high-absorbency
material commonly known as superabsorbent material. In a particular
embodiment, the absorbent assembly 44 comprises a matrix of
cellulosic fluff, such as wood pulp fluff, and superabsorbent
hydrogel-forming particles. The wood pulp fluff can be exchanged
with synthetic, polymeric, meltblown fibers or short cut homofil
bicomponent synthetic fibers and natural fibers. The superabsorbent
particles can be substantially homogeneously mixed with the
hydrophilic fibers or can be nonuniformly mixed. The fluff and
superabsorbent particles can also be selectively placed into
desired zones of the absorbent assembly 44 to better contain and
absorb body exudates. The concentration of the superabsorbent
particles can also vary through the thickness of the absorbent
assembly 44. Alternatively, the absorbent assembly 44 can comprise
a laminate of fibrous webs and superabsorbent material or other
suitable means of maintaining a superabsorbent material in a
localized area.
Suitable superabsorbent materials can be selected from natural,
synthetic, and modified natural polymers and materials. The
superabsorbent materials can be inorganic materials, such as silica
gels, or organic compounds, such as crosslinked polymers, for
example, sodium neutralized polyacrylic acid. Suitable
superabsorbent materials are available from various commercial
vendors, such as Dow Chemical Company located in Midland, Mich.
U.S.A., and Stockhausen GmbH & Co. KG, D-47805 Krefeld, Federal
Republic of Germany. Typically, a superabsorbent material is
capable of absorbing at least about 15 times its weight in water,
and desirably is capable of absorbing more than about 25 times its
weight in water.
In one embodiment, the absorbent assembly 44 is generally
rectangular in shape, and comprises a blend of wood pulp fluff and
superabsorbent material. One preferred type of pulp is identified
with the trade designation CR1654, available from U.S. Alliance,
Childersburg, Ala. U.S.A., and is a bleached, highly absorbent
sulfate wood pulp containing primarily soft wood fibers and about
16 percent hardwood fibers. As a general rule, the superabsorbent
material is present in the absorbent assembly 44 in an amount of
from about 5 to about 90 weight percent based on total weight of
the absorbent assembly. The absorbent assembly 44 suitably has a
density within the range of about 0.10 to about 0.35 grams per
cubic centimeter. The absorbent assembly 44 may or may not be
wrapped or encompassed by a suitable tissue wrap that may help
maintain the integrity and/or shape of the absorbent assembly.
The absorbent body 32 can also incorporate other materials that are
designed primarily to receive, temporarily store, and/or transport
liquid along the mutually facing surface with absorbent assembly
44, thereby maximizing the absorbent capacity of the absorbent
assembly. One suitable material is referred to as a surge layer
(not shown) and comprises a material having a basis weight of about
50 to about 120 grams per square meter, and comprising a
through-air-bonded-carded web of a homogenous blend of 60 percent 3
denier type T-256 bicomponent fiber comprising a polyester
core/polyethylene sheath and 40 percent 6 denier type T-295
polyester fiber, both commercially available from Kosa Corporation
of Salisbury, N.C. U.S.A.
As noted previously, the illustrated training pant 20 has front and
back side panels 34 and 134 disposed on each side of the absorbent
body 32. These transversely opposed front side panels 34 and
transversely opposed back side panels 134 can be permanently bonded
along attachment lines 66 to the composite structure 33 of the
absorbent body 32 in the respective front and back waist regions 22
and 24. More particularly, as shown best in FIGS. 2 and 3, the
front side panels 34 can be permanently bonded to and extend
transversely beyond the linear side edges 47 of the composite
structure 33 in the front waist region 22, and the back side panels
134 can be permanently bonded to and extend transversely beyond the
linear side edges of the composite structure in the back waist
region 24. The side panels 34 and 134 may be attached using
attachment means known to those skilled in the art such as
adhesive, thermal or ultrasonic bonding. Alternatively, the side
panels 34 and 134 can be formed as a portion of a component of the
composite structure 33. For example, the side panels can comprise a
generally wider portion of the outer cover, the bodyside liner,
and/or another component of the absorbent body. Thus, the pant 20
can include a one-piece chassis, such as an allover stretch outer
cover.
The illustrated side panels 34 and 134 each define a distal edge 68
that is spaced from the attachment line 66, a leg end edge 70
disposed toward the longitudinal center of the training pant 20,
and a waist end edge 72 disposed toward a longitudinal end of the
training pant. The leg end edge 70 and waist end edge 72 extend
from the side edges 47 of the composite structure 33 to the distal
edges 68. The leg end edges 70 of the side panels 34 and 134 form
part of the side edges 36 of the absorbent body 32. In the back
waist region 24, the leg end edges 70 are desirably although not
necessarily curved and/or angled relative to the transverse axis 49
to provide greater coverage toward the back of the pant as compared
to the front of the pant. The waist end edges 72 are desirably
parallel to the transverse axis 49. The waist end edges 72 of the
front side panels 34 form part of the front waist edge 38 of the
absorbent body 32, and the waist end edges 72 of the back side
panels 134 form part of the back waist edge 39 of the absorbent
body.
In particular embodiments for improved fit and appearance, the side
panels 34 and 134 desirably have an average length dimension
measured parallel to the longitudinal axis 48 that is about 20
percent or greater, and particularly about 25 percent or greater,
of the overall length dimension of the absorbent article, also
measured parallel to the longitudinal axis 48. For example, in
training pants having an overall length dimension of about 54
centimeters, the side panels 34 and 134 desirably have an average
length dimension of about 10 centimeters or greater, such as about
15 centimeters. While each of the side panels 34 and 134 extend
from the waist opening 50 to one of the leg openings 52, the back
side panels 134 have a continually decreasing length dimension
moving from the attachment line 66 to the distal edge 68, as is
best shown in FIGS. 2 and 3.
Each of the side panels 34 and 134 can include one or more
individual, distinct pieces of material. In particular embodiments,
for example, each side panel 34 and 134 can include first and
second side panel portions that are joined at a seam, or can
include a single piece of material which is folded over upon itself
(not shown). The side panels 34 and 134 desirably although not
necessarily comprise an elastic material capable of stretching in a
direction generally parallel to the transverse axis 49 of the
training pant 20. Solely by way of illustration, suitable elastic
side panels 34 and 134 can be stretchable from about 150 percent to
about 450 percent. This means that a panel having a relaxed length
of 10 millimeters (mm) when stretched 5 mm would have been
stretched 150 percent of its original length. Elastic materials if
provided over the entire front and/or back region of pant 20 could
fit well with lower stretch, for example from about 150 percent to
about 250 percent. In embodiments where the entire front and/or
back region panel is not stretchable, then higher levels of
stretch, for example, about 250 percent to about 450 percent may be
preferred.
Suitable elastic materials, as well as one process of incorporating
elastic side panels into a training pant, are described in the
following U.S. Pat. No. 4,940,464 issued Jul. 10, 1990 to Van
Gompel et al.; U.S. Pat. No. 5,224,405 issued Jul. 6, 1993 to
Pohjola; U.S. Pat. No. 5,104,116 issued Apr. 14, 1992 to Pohjola;
and U.S. Pat. No. 5,046,272 issued Sep. 10, 1991 to Vogt et al.;
all of which are incorporated herein by reference. In particular
embodiments, the elastic material comprises a stretch-thermal
laminate, a neck-bonded laminate, a reversibly necked laminate, or
a stretch-bonded laminate material. Methods of making such
materials are well known to those skilled in the art and described
in U.S. Pat. No. 4,663,220 issued May 5, 1987 to Wisneski et al.;
U.S. Pat. No. 5,226,992 issued Jul. 13, 1993 to Mormon; and
European Patent Application No. EP 0 217 032 published on Apr. 8,
1987 in the names of Taylor et al.; all of which are incorporated
herein by reference. Alternatively, the side panel material may
comprise other woven or nonwoven materials, such as those described
above as being suitable for the outer cover 40 or bodyside liner
42; mechanically prestrained materials; and/or stretchable but
inelastic materials.
In particular embodiments, one or more of the side panels 34 and
134 can be formed of retractive materials. For example, the side
panels 34 and 134 can be formed of an elastomeric material that is
adapted to retract upon activation by a source of heat, such as
disclosed in U.S. Pat. No. 4,640,726.
The illustrated training pant 20 includes a fastening system 80 for
refastenably securing the training pant about the waist of the
wearer. The illustrated fastening system 80 includes first
fastening components 82 and 83 that are adapted to refastenably
connect to mating second fastening components 84 and 85. In one
embodiment, one surface of each of the first fastening components
82 and 83 comprises a plurality of engaging elements that project
from that surface. The engaging elements of the first fastening
components 82 and 83 are adapted to repeatedly engage and disengage
engaging elements of the second fastening components 84 and 85.
In one particular embodiment, the first fastening components 82 and
83 each comprise hook type fasteners and the second fastening
components 84 and 85 each comprise complementary loop type
fasteners. In another particular embodiment, the first fastening
components 82 and 83 each comprise loop type fasteners and the
second fastening components 84 and 85 each comprise complementary
hook type fasteners. Although the illustrated embodiments show the
back waist region 24 overlapping the front waist region 22, which
is convenient, the training pant 20 can also be configured so that
the front waist region overlaps the back waist region.
Hook type fasteners typically comprise a fabric or material having
a base or backing structure and a plurality of hook members
extending upwardly from at least one surface of the backing
structure. The hook material advantageously comprises a resilient
material to minimize unintentional disengagement of the fastener
components as a result of the hook material becoming deformed and
catching on clothing or other items. The term "resilient" as used
herein refers to an interlocking material having a predetermined
shape and the property of the interlocking material to resume the
predetermined shape after being engaged and disengaged from a
mating, complementary interlocking material. Suitable hook material
can be molded or extruded of nylon, polypropylene or another
suitable material. Suitable single-sided hook materials for the
fastening components 82-85 are available from commercial vendors
such as Velcro Industries B.V., Amsterdam, Netherlands or
affiliates thereof, and are identified as Velcro HTH829 with a
uni-directional hook pattern and having a thickness of about 0.9
millimeters (35 mils) and HTH-851 with a uni-directional hook
pattern and having a thickness of about 0.5 millimeters (20 mils);
and Minnesota Mining & Manufacturing Co., St. Paul, Minn.
U.S.A., including specific materials identified as CS-600. Hook
materials could be made with elastic material with base polymer
such as urethane, KRAYTON or PEBAX.
In accordance with the present invention, the loop type fastener is
preferably made of a stretchable or extensible material which may
include a stretch bonded laminate, and which may be elastomeric. In
particular embodiments, the loop material can be mounted to a base
of stretchable material so the assembly is stretchable.
Alternatively, the loop material may be a retractable material
which retracts on application of heat as described more fully below
in connection with one particular embodiment.
With particular reference to FIG. 3, the first fastening components
82 and 83 are desirably although not necessarily disposed on the
inner surface 28 of the training pant 20 in the back waist region
24. The first fastening components 82 and 83 are desirably
positioned along the distal edges 68 of the back side panels 134,
and abutting or adjacent to the waist end edge 72. In certain
embodiments, for example, the first fastening components 82 and 83
can be located within about 2 centimeters, and more particularly
within about 1 centimeter, of the distal edges 68, the waist end
edges 72, and the leg end edges 70.
With particular reference to FIG. 2, the second fastening
components 84 and 85 are desirably although not necessarily
disposed on the outer surface 30 of the training pant 20 in the
front waist region 22, although it is contemplated that the
fastening components can be placed anywhere on the pant so long as
they help to hold the pant on the wearer. The second fastening
components 84 and 85 are sized to receive the first fastening
components 82 and 83 and are desirably positioned along the distal
edges 68 of the front side panels 34, and abutting or adjacent to
the waist end edge 72. In certain embodiments, for example, the
second fastening components 84 and 85 can be located within about 2
centimeters, and more particularly within about 1 centimeter, of
the distal edges 68, the waist end edges 72, and the leg end edges
70. Where the first fastening components 82 and 83 comprise loop
type fasteners disposed on the inner surface 28 and the second
fastening components 84 and 85 comprise hook type fasteners
disposed on the outer surface 30, the first fastening components
can be sized larger than the second fastening components to ensure
coverage of the rigid, outwardly-directed hooks. The loop fastening
components can be integral with the side panels or adhered to the
side panels 34 and 134 by any means known to those skilled in the
art such as adhesive bonds, sonic bonds or thermal bonds. The loop
fastening components can be extensible and bonded to components of
the body 32 in a manner that retains extension and retraction
characteristics of the loop fastening components.
The fastening components are desirably rectangular, although they
may alternatively be square, round, oval, curved or otherwise
non-rectangularly shaped. In particular embodiments, each of the
fastening components 82-85 defines a length dimension aligned
generally parallel with the longitudinal axis 48 of the training
pant 20 and a width dimension aligned generally parallel with the
transverse axis 49 of the training pant. For a child of about 9 to
about 15 kilograms (20-30 pounds), for example, the length
dimension of the fastening components is desirably from about 5 to
about 13 centimeters, such as about 10 centimeters, and the width
dimension is desirably from about 0.5 to about 3 centimeters, such
as about 1 centimeter. With particular embodiments, the fastening
components can have a length-to-width ratio of about 2 or greater,
such as about 2 to about 25, and particularly about 5 or greater,
such as about 5 to about 8. For other embodiments such as for adult
products, it may be desirable for one or more of the fastening
components to comprise a plurality of relatively smaller fastening
elements. In that case, a fastening component or individual
fastening elements may have an even smaller length-to-width ratio,
for example, of about 2 or less, and even about 1 or less.
When the fastening components 82-85 are releasably engaged, the
side edges 36 of the absorbent body 32 in the crotch region 26
define the leg openings 52, the waist edges 38 and 39 of the
absorbent body, including the waist end edges 72 of the side
panels, define the waist opening 50, and the waist regions 22 and
24 jointly define a waistband 75 and hip section 77. For improved
formation of the leg openings 52, it can be desirable in some
embodiments for the front side panels 34 to be longitudinally
spaced from the back side panels 134 (see FIGS. 2 and 3). For
example, the front side panels 34 can be longitudinally spaced from
the back side panels 134 by a distance equal to about 20 percent or
greater, particularly from about 20 to about 60 percent, and more
particularly from about 35 to about 50 percent, of the overall
length dimension of the absorbent article.
When connected, the fastening components 82-85 form refastenable
seams 88 (FIG. 1) that desirably although not necessarily extend
substantially the entire distance between the waist opening 50 and
the leg openings 52. More specifically, the refastenable seams 88
can cover about 80 to 100 percent, and particularly about 90 to
about 98 percent, of the distance between the waist opening 50 and
each leg opening 52, which distance is measured parallel to the
longitudinal axis 48. To construct the seams 88 to extend
substantially the entire distance between the waist and leg
openings 50 and 52, the fastening components 82-85 can be formed to
cover about 80 to 100 percent, and more particularly about 90 to
about 98 percent, of the distance between the waist end edge 70 and
the leg end edge 72 of the side panels 34 and 134. In other
embodiments, the fastening components can comprise a plurality of
smaller fastening elements covering a smaller portion of the
distance between the waist opening 50 and the leg openings 52, for
example, about 20 to about 70 percent, but spaced apart to span a
larger percentage of the distance between the waist opening and the
leg openings.
For the refastenable seams 88 to be located at the sides of the
wearer, it can be particularly desirable for the transverse
distance between the first fastening components 82 and 83 to be
substantially equal to the transverse distance between the second
fastening components 84 and 85. The transverse distance between a
set of fasteners is the distance measured parallel to the
transverse axis 49 between the longitudinal centerlines of the
fasteners, measured with the side panels 34 and 134 in an
unstretched condition. In an alternative embodiment, the training
pant 20 includes only a single second fastening component disposed
in the front waist region 22 for refastenably connecting the first
fastening components 82 and 83 (not shown).
In a further alternative embodiment illustrated in FIGS. 4 and 5,
one or both of the fastening components can comprise integral
portions of the waist regions. For instance, one of the elastomeric
front or back side panels 34 and 134, respectively, can function as
second fastening components in that they can comprise a material
that is releasably engageable with fastening components disposed in
the opposite waist region. As illustrated in FIGS. 4 and 5, the
side panels 134 are made completely of stretchable loop material
although, alternatively, these side panels could be made of loop
material only at their outer ends where they will engage the hook
material and the remainder of the side panels can be made of some
other, preferably stretchable, material and joined along abutting
edges thereof.
FIG. 6 schematically illustrates a flow diagram for manufacture of
one embodiment of a pant according to the present invention. The
components of the pants 20 can be provided and bonded together in
an assembly section 200, typically in the form of a continuous web
of interconnected and partially assembled pants. The assembly
section 200 can include a cutting mechanism which selectively cuts
the web into discrete, partially assembled training pants.
The discrete training pants can then be folded at a folding station
202 using any suitable folding mechanism. The training pants 102
can be folded about a fold line generally bisecting the training
pants. As such, the waist regions 22 and 24 of each training pant
can be positioned in facing relationship with the side panels 34
and 134 extending laterally outward relative to the longitudinal
axis 48 of the training pant. The fold line can extend in a lateral
direction through the crotch region 26 of the training pant.
Desirably, the discrete training pants are consistently folded
about the fold line such that the front and back waist edges 38 and
39 of the training pants align with each other.
The opposed side panels 34 and 134 can also be folded in the
folding section 202. The side panels 34 and 134 can desirably be
folded parallel to the longitudinal centerline of the training
pants so that at least portions of the first and second fastening
components overlap with one another. The side panels 34 and 134 can
alternatively be folded together in conjunction with engagement of
the first and second fastening components 82-85 in a seaming
section 204. The seaming section 204 forms the refastenable seams
88 of the pants 20. Suitable devices to inwardly fold the side
panels 34 and 134 parallel to the longitudinal centerline can
include folding boards, folding skis, paddles, fingers, vacuum
devices, air blasts, mechanical devices with reciprocating motion
such as tuckers, four-bar linkages, slide-crank mechanisms, or the
like and combinations thereof which are preferably adapted to
stretch or extend the fastening component formed of loop material
prior to its being placed on the fastening component formed of hook
material.
The training pants 20 can be transported to an activation station
206, which can but need not necessarily follow the seaming section
204 as illustrated. The activation station 206 can comprise an
activation source such as a heating unit to instigate retraction of
the retractive material in those constructions which use a heat
activated retractive material in any components of the pants 20,
including the loop-type fastening material. It is contemplated that
materials which shrink or contract through other means can also be
utilized in the present invention, such as disclosed in U.S. Pat.
No. 4,883,549, incorporated herein by reference, or simply by slow
responding material. The activation station 206 can comprise a
separate stage of the manufacturing operation or can be
incorporated into another stage. In particular embodiments, the
activation station 206 can be combined with devices such as product
stackers for packaging the pants 20. Suitable devices incorporating
activation mechanisms are disclosed in U.S. Pat. No. 4,640,726
issued Feb. 3, 1987 to Sallee et al. and U.S. Pat. No. 4,663,106
issued May 5, 1987 to Pomplun et al., which are incorporated herein
by reference. In the illustrated embodiment, at least a portion of
the retractive material is activated and caused to retract
subsequent to engagement of the fastening components 82-85. While
the loop-type fastening material was described in particular
embodiments as comprising a retractive material, other components
of the training pant such as distinct elements or portions of the
outer cover, bodyside liner, absorbent assembly, waist elastics,
side panels or fastening components can alternatively or
additionally comprise retractive materials.
FIG. 7 illustrates a training pant 300 at three stages during
manufacture, denoted with reference numerals 301, 302 and 303. The
training pant 300 is similar to the training pant 20 shown in FIG.
1, although the front side panels 34 are narrower than the back
side panels 134. The training pant 300 at stage 301 has been folded
through the crotch region 26 to overlap the waist regions 22 and 24
and the hip regions. At stage 302, one or both pairs of side panels
34 and 134 of the training pant 300 can be folded along fold lines
306 which are parallel to the longitudinal centerline 308 of the
training pant. With the fastening components 82-85 engaged, the
waist regions 22 and 24 define the waistband 75 and hip section 77,
both of which encircle the pant 300 between the crotch region 26
and the waist opening. The waistband 75 is contiguous with the
waist opening 50 (FIG. 1) while the hip section 77 is disposed
between the waistband and the leg openings 52 (FIG. 1). At stage
303, the retractive materials forming the waist elastic members 54
and 56, the side panels 34 and 134, and/or other components, such
as loop-type fastening material, can be activated and the
retractive materials allowed to retract.
When the training pants 20, or other garment formed in accordance
with the present invention, are manually formed into a three
dimensional garment to fit a wearer, as illustrated in FIG. 1, by
manual manipulation as the garment is being placed on the wearer
the fastening components 82 and 83 that contain the loop material
and rear side panels 134 are stretched toward the front side panels
34 and then applied to the respective hook material 84 and 85 on
the front side panels 34. The loop material and side panels are
then released and allowed to contract on the hook material to
produce a mechanical fastener system which exhibits greater
engagement strength than conventional mechanical fastening systems.
Alternatively, it is contemplated that the loop material can be
held under tension and the hook material applied to it or any other
means for causing engagement between the hook and loop material
while the loop material is in an extended or stretched state and
then allowed to retract.
As discussed above, it is also contemplated that when the training
pants or the like garment are being initially constructed and
folded by machine, the loop material and/or its underlying support
material of the various embodiments described above can be extended
and placed in engagement with the hook material and then pressed
thereon to give an initial construction that is stronger in the
mechanical fastener system than conventional mechanical fastening
systems. Also as mentioned above, in an alternative embodiment
where the garment is constructed and assembled by machine the loop
material may be a retractive material that is simply placed on the
hook material during making of the garment and then the hook
material can be shrunk by an application of heat to embed the hooks
into the loop material. Alternatively, as mentioned above, the loop
material can retract in other ways, such as temporarily inhibiting
retraction of a stretched elastic member as described in U.S. Pat.
No. 4,883,549, or other means such as light motion, pressure
exerted, etc.
It is believed that the stretch in the loop material increases the
amount of engagement such a fastening system obtains, reducing the
occurrence of "pop opens" (refastenable side panels with
hook-and-loop disengaging) over conventional hook-and-loop
fasteners.
It is believed that a wide range of hook-and-loop materials would
be suitable for use in the present invention, so long as the loop
material is sufficiently stretchable to exhibit the desired
enhanced engagement capabilities that produce the desired reduction
in "pop opens" over conventional hook-and-loop fasteners. For
example, in the embodiment of FIGS. 3 and 4, it is desirable that
the loop material side panels exhibit a high stretchability of
approximately 150 to 300 percent although greater stretchability
such as from 300 to 450 percent of at least the loop portion of the
side panel, can be exhibited by the material. In its preferred form
it is desirable that the loop material be constructed of an
extensible material such as but not limited to a stretch bonded
material.
While the mechanical fastening means of the present invention are
shown and described herein in connection with children's toilet
training pants, it is understood that such fastening means may be
incorporated into various other disposable absorbent articles, such
as diapers, adult incontinence garments, sanitary napkins and the
like, as well as surgical bandages and sponges, without departing
from the scope of the present invention.
As various changes could be made in the above constructions and
methods, without departing from the scope of the invention, it is
intended that all matter contained in the above description and
shown in the accompanying drawings shall be interpreted as
illustrative and not in a limiting sense.
When introducing elements of the present invention or the preferred
embodiment(s) thereof, the articles "a", "an", "the" and "said" are
intended to mean that there are one or more of the elements. The
terms "comprising", "including" and "having" are intended to be
inclusive and mean that there may be additional elements other than
the listed elements.
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